I wonder if they were actually sandhill cranes- they are pretty similiar,make practically the same noise and their numbers have increased a lot, while I think that the whooping cranes haven't.
Sandhill cranes winter in southern Colorado and flocks of them fly right over our house in the fall. It's almost prehistoric- they make an unreal whooping sound, and they have to wait until it warms up to take off because they are so big.
Ah, I don’t know, I thought they were geese at first (I see double and have problems with distance). Didn’t hear the whooping, and it was so windy that the sound may have traveled the other way.